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by Hertwig's and Morgan's modifications of the bio-
genetic law, which, in turn, are of a merely hypotheti-
cal nature. In addition to this a short reference to
Weismann's "confirmation" of Haeckel's law may be
useful. Weismann knew that in the larval develop-
ment of certain butterflies transverse stripes were pre-
ceded by longitudinal ones. Hence he concluded that
in certain similar butterflies, whose early larval stages
were then unknown, a similar succession of markings
ought to be found. Ten years later the " predicted "
marking was discovered. It is plain that such facts
are no confirmation of the biogenetic law, but find their
simple explanation in the fact that similar organisms
will show similar ontogenetic stages. This fact, too,
seems to account sufficiently for the observations
advanced by Morgan in support of his theory of repe-
tition.
VII. The Biogeogr.\phical Argument. — The bio- geographical argument is a very complex one, com- posetl of a vast number of single facts whose correla- tion among one another, and whose bearing upon the problem of evolution, can hardly be determined before many years of detailed research have gone by. The theories established, for instance, by Wallace are cer- tainly not sufficiently supported by facts. On the contrary, they have serious defects. One of them is the well-knowii "Wallace line"; another, much more important, the unfounded assertion that the higher vertebrates must have originated from marsupials and monotremes because these animals are almost entirely extinct in all countries except in isolated Australia, where they survive, as the highest representatives of the Australian vertebrates, m greatly varying forms till to-day. Besides, in most cases we have no suffi- cient knowledge of the geographical distribution of organisms and of its various causes. But in order to give the reader an idea of the argument, we shall briefly refer him to a group of facts which is well adapted to support the view of evolution explained in the preceding pages. Volcanic islands and such as are separated from the continent by a sea or strait of great depth exhibit a fauna and flora which have certainly come from the neighbouring continents, but which at the same time possess features altogether peculiar to them. The flora of Socotra, in the Indian Ocean, for instance, comprises 565 systematic species; among these there are 206 endemic ones. Similarly, on Mada- gascar there are 3000 endemic plant-species among 4100; on the Hawaian Islands, 70 endemic species of birds among 116; on the Galapagos, S-1 among lOS. Many such facts are known. They certainly form an excellent demonstration in favour of the proposition defended throughout this article: that such forms as the endemic species, which may well be compared with the races of the human species, were not directly created, but arose by some process of modification which was greatly facilitated by their complete isola- tion.
The most important General Conclusions to be noted are as follows: —
1. The origin of life is unknown to science.
2. The origin of the main organic types and their principal subdivisions are likewise unknown to science.
3. There is no evidence in favour of an ascending evolution of organic forms.
4. There is no trace of even a merely probable argu- ment in favour of the animal origin of man. The earliest human fossils and the most ancient traces of culture refer to a true Homo sapiens as we know him to-day.
5. Most of the so-called systematic species and genera were certainly not created as such, but origi- nated by a process of either gradual or saltatory evolu- tion. Changes which extend beyond the range of variation observed in the human species have thus far not been strictly demonstrated, either experimentally or historically.
6. There is very little known as to the causes of evo-
lution. The greatest difficulty is to explain the origin
and constancy of "new" characters and the teleology
of the process. Darwin's " natural selection " is a neg-
atife factor only. The moulding influence of the en-
vironment cannot be doubted ; but at present we are un-
able to ascertain how far that influence may extend.
Lamarck's " inheritance of acquired characters" is not
yet exactly proved, nor is it evident that really new
forms can arise by "mutation". In our opinion the
principal of "Mendelian segregation", together with
Darwin's natural selection and the moulding influence
of environment, will probably be some of the chief
constituents of future evolutionary theories.
Many works referring to the subject have been mentioned in the body of the article. We shall here enumerate mainly such as are of more recent date and will be of special value for further study.
General. — Ger.\rd. The Old Riddle and the Newest Answer (London, 1908); Gutberlet, Der Mensch, sein Ursprung und seine Entwicklung iPaderhoTn. 1896); Kerner von Marilaun, Pflamenleben (Leipzig and Vienna, 1890-91), II; Mivart, On the Genesis of Species (London, 1S71): Wasmann. Die modeme Biologie und die Entmcklungslheorie (Freiburg, 1906); Id., Der Kampf um das Entwicklungsprohlem in Berlin (Freiburg. 1907); Qu.vtrefages. U Espeee humaine (Paris. 1880); Zapletal, Der Schiipfungsbericht (Freiburg, 1902); Morgan, Evolution and Adaptation (New York. 1903); Lotsy. Vorlesungen iiber De- scendenztheorien (Jena, 1908); Kohlbrugge, Die morpholo- gische Abstammung des Menschen (Stuttgart, 1908); Die Deszen- denztheorie (Leipzig, 1901); Osborn, From the t^reeks to Darwin (New York, 1905); Hartmanx, Das Problem des Lebens (Bad Sachsa, 1906); Brooks, The Foundation of Zoology (New York, 1899); Wilson, The Cell (New York, 1906); Hertwig, All- gemeine Biologie (Jena, 1906); Id., Die Elemente der Entwick- lungslehre des Menschen und der Wirheltiere (Jena, 1900); KoRSCHELT AND Heider, Lehrbuch der vergleichenden Entwick- lungsgeschichte der Wirbelosen Tiere (Jena, 1902-03); Reinke, Einleiiung in theoretische Biologie (Berlin, 1901); F. Darwin, The Life and Letters of Charles Darwin (London, 1887); Id. and Seward, More Letters of Charles Darwin (London, 1908); Weismann, Vortrdge iiber Deszendenztheorie (Jena, 1904); Fleischmann, Die Darwinsche Theorie (Leipzig, 1903); Plate, Selektionsprinzip und Probleme der Artbildu7ig (Leipzig, 1908).
Experimental Evidence. — Lock, Recent Progress in the Study of Variation, Heredity, and Evolution (London, 1907) ; Mucker- mann. Variabilitdt und Artbildung in Natur und Offenb. (Miin- ster, Jan.. 1909); de Vries. Die MiUationstheorie (Leipzig, 190i-03); Johannsen. Ueber Erblichkeit in Populationen und in reinen Linien (Jena, 1903); Wasmann, Gibt es tatsdchlich Arten^ etc., in Biol. Zentralbl. (1901); Galton, Natural Inheritance (London, 1889); Mendel, Versuche iiber Pflanzenhybriden, in Ostwolds Klassiker, No. 121; Bateson, Mendel's Principles of Heredity (Cambridge, 1902); Id., The Progress of Genetics since the Rediscovery of MendeVs Papers, in Progressus Rei Botanicce (Jena. 1907), I, 386; Correns. Ueber Vererbungsgesetze (Berlin, 1906); Padtberg and Muckermann, Mendel und Mendelismus (Munieh, 1909); Gross, Ueber einige Beziehungen zwischen Vererbung und Variation, in Biol. Zentralbl. (1906); Strasbur- ger. Die stofflichen Grundlagen der Vererbung (Jena, 1905); Ziegler._ Die Vererbungslehre in der Biologie (Jena. 1905).
Historical Evidence. — Muckermann, Paldontologische Ur- kunden und das Problem der Artbildung, in Stimm. aus Maria Laach, Jan., 1909; Steinmann, Die geologischen Grundlagen der Abstammungslehre (Leipzig, 1908); Laurent, Les progr^s de la paleobotanique angiospermique dans la demitre decade, in Progr. R. Bot. (Jena, 1907), I; Koken, Die Vorwelt und ihre Entwick- lungsgeschichte (Leipzig, .15^3); Id., Paliiontologie 'und Deszen- denzlehre (Jena, 1902); Zittel. Palaozoologie (Munich and Leipzig. 1876-93); Schimper and Schenk, Palaophytologie (Munich and Leipzig, 1890); de Lapparent, Traite de geologic (Paris, 1900); Dana, Manual of Geology (New York, — ); Geikie, Text-hook of Geology (London. 1893); Cope, The Pri- mary Factors of Organic Evolution (Chicago, 1895); Steinmann, EinjiiJirung in die Palaontologie (Leipzig, 1907); Credner, Etc- mente der Geologie (Leipzig); Kayser, Geologi.'iche Formations' kunde (Stuttgart, 1908); Neumayr, Brdgeschichte (Leipzig, 1887): Scharff, European Animals: their Geological History and Geographical Distribution (London, 1907); Ward, Sketch of Paleobotany (Washington, 1885); Handlirsch, Die fossilen Insekten und die Phylogenie der rezenten Formen (Leipzig, 190S); IIoERNES, Der dilui'iale Mensch (Brunswick, 1903); Schimpfer, Pflanzengeographie (Jena. 1908); Lydekker, A Geographical History of Mammals (London, 1896).
H. Muckermann.
Evora, Archdiocese op, in Portugal, raised to archiepiscopal rank in 1544, at which time it was given ;is sulTragans Leiria and Portalegre; in 1570 and later were added Sylves, Ceuta, Congo, Santo Thomd, Furichal. Cabi) Verde, and Angra. In the Roman period .Julius Caesar gave it the name of Liberalitas Julia; inscriptions and coins remain to prove its high rank among the municipalities of Roman Spain. It8
